Auditory navigation with a tubular acoustic model for interactive distance cues and personalized head-related transfer functions
Authors:Geronazzo M., Avanzini F., Fontana F.
Published in:Journal on Multimodal User Interfaces, May 2016, pp. 1-12.
Abstract:This paper presents a novel spatial auditory display that
combines a virtual environment based on a Digital Waveguide Mesh (DWM)
model of a small tubular shape with a binaural rendering system with
personalized head-related transfer functions (HRTFs) allowing
interactive selection of absolute 3D spatial cues of direction as well
as egocentric distance. The tube metaphor in particular minimizes
loudness changes with distance, providing mainly direct-to-reverberant
and spectral cues. The proposed display was assessed through a
target-reaching task where participants explore a 2D virtual map with a
pen tablet and hit a sound source (the target) using auditory
information only; subjective time to hit and traveled distance were
analyzed for three experiments. The first one aimed at assessing the
proposed HRTF selection method for personalization and dimensionality of
the reaching task, with particular attention to elevation perception; we
showed that most subjects performed better when they had to reach a
vertically unbounded (2D) rather then an elevated (3D) target. The
second experiment analyzed interaction between the tube metaphor and
HRTF showing a dominant effect of DWM model over binaural rendering. In
the last experiment, participants using absolute distance cues from the
tube model performed comparably well to when they could rely on more
robust, although relative, intensity cues. These results suggest that
participants made proficient use of both binaural and reverberation cues
during the task, displayed as part of a coherent 3D sound model, in
spite of the known complexity of use of both such cues. HRTF
personalization was beneficial for participants who were able to
perceive vertical dimension of a virtual sound. Further work is needed
to add full physical consistency to the proposed auditory display.
